Submission #1209460

#	Time	Username	Problem	Language	Result	Execution time	Memory
1209460		JooDdae	Two Antennas (JOI19_antennas)	C++20	100 / 100	477 ms	32488 KiB

antennas

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#define mid ((l+r) >> 1)

const int INF = 1e9;

int n, m, a[200200], b[200200], h[200200], ans[200200], t[800800], t2[800800], lz[800800];
vector<int> in[200200], out[200200];

void lazy_update(int node, int l, int r) {
    if(lz[node]) {
        t2[node] = max(t2[node], lz[node]-t[node]);
        if(l != r) lz[node*2] = max(lz[node*2], lz[node]), lz[node*2+1] = max(lz[node*2+1], lz[node]);
        lz[node] = 0;
    }
}

void update(int nl, int nr, int val, int node = 1, int l = 1, int r = n) {
    lazy_update(node, l, r);
    if(nr < l || r < nl) return;
    if(nl <= l && r <= nr) {
        lz[node] = max(lz[node], val);
        lazy_update(node, l, r);
        return;
    }
    update(nl, nr, val, node*2, l, mid), update(nl, nr, val, node*2+1, mid+1, r);
    t[node] = min(t[node*2], t[node*2+1]);
    t2[node] = max(t2[node*2], t2[node*2+1]);
}

void update2(int id, int val, int node = 1, int l = 1, int r = n) {
    lazy_update(node, l, r);
    if(id < l || r < id) return;
    if(l == r) {
        t[node] = val;
        lazy_update(node, l, r);
        return;
    }
    update2(id, val, node*2, l, mid), update2(id, val, node*2+1, mid+1, r);
    t[node] = min(t[node*2], t[node*2+1]);
    t2[node] = max(t2[node*2], t2[node*2+1]);
}

int find(int nl, int nr, int node = 1, int l = 1, int r = n) {
    lazy_update(node, l, r);
    if(nr < l || r < nl) return -INF;
    if(nl <= l && r <= nr) return t2[node];
    return max(find(nl, nr, node*2, l, mid), find(nl, nr, node*2+1, mid+1, r));
}

void solve(vector<array<int, 3>> q) {
    fill(t, t+4*n+1, INF+10), fill(t2, t2+4*n+1, -INF);
    fill(lz, lz+4*n+1, 0);

    int L = 0;
    for(auto [r, l, id] : q) {
        while(L < r) {
            int u = ++L;
            for(auto x : in[u]) update2(x, h[x]);
            for(auto x : out[u]) update2(x, INF+10);
            update(max(1, u-b[u]), max(0, u-a[u]), h[u]);
        }
        ans[id] = max(ans[id], find(l, r));
    }
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin >> n;
    for(int i=1;i<=n;i++) cin >> h[i] >> a[i] >> b[i];
    for(int i=1;i<=n;i++) if(i+a[i] <= n) in[i+a[i]].push_back(i);
    for(int i=1;i<=n;i++) if(i+b[i] <= n) out[i+b[i]+1].push_back(i);

    cin >> m;
    vector<array<int, 3>> q(m);
    for(int i=0;i<m;i++) cin >> q[i][1] >> q[i][0], q[i][2] = i;
    sort(q.begin(), q.end());

    memset(ans, -1, sizeof ans);
    solve(q);
    for(int i=1;i<=n;i++) h[i] = INF-h[i]+1;
    solve(q);
    for(int i=0;i<m;i++) cout << ans[i] << "\n";
}

• Subtask 1: 2 / 2
• Subtask 2: 11 / 11
• Subtask 3: 22 / 22
• Subtask 4: 65 / 65